The prior art is replete with electronic display systems and various applications for their use. Display systems are often used in a manufacturing setting, for diagnostic and research equipment, in navigation systems, in entertainment systems, and in vehicles. For instance, modern flight deck displays (or cockpit displays) for vehicles (such as aircraft or spacecraft) display a considerable amount of information, such as vehicle position, speed, altitude, attitude, navigation, target, and terrain information. In the case of an aircraft, most modern displays additionally display a flight plan from different views, either a lateral view, a vertical view, or a perspective view, which can be displayed individually or simultaneously on the same display. The perspective view provides a three-dimensional view of the vehicle flight plan (or vehicle forward path) and may include various map features including, for example, weather information, terrain information, political boundaries, and navigation aids (e.g., waypoint symbols, line segments that interconnect the waypoint symbols, and range rings). The terrain information may include a synthetic representation of terrain, as well as terrain cautions and warnings which, among other things, may indicate terrain that may obstruct the current flight path of the aircraft. The primary perspective view used in existing synthetic vision systems emulates a forward-looking cockpit viewpoint. Such a view is intuitive and provides helpful visual information to the pilot and crew.
A vehicle such as an aircraft may also utilize onboard sensors and systems (e.g., radar, light detection and ranging (lidar), laser detection and ranging (ladar) in military contexts, infrared (IR), ultraviolet (UV), and the like) to augment or enhance the forward-looking cockpit view and provide a visual representation of obstacles, objects, and other man-made and/or non-terrain features within the aircraft's current operating environment which may or may not be accounted for in the various databases (e.g., terrain databases, obstacle databases, airport databases, and the like) used for rendering the synthetic perspective view. These enhanced vision systems are particularly useful when operating a vehicle or aircraft in conditions of reduced visibility, such as, for example, whiteout, brownout, sea-spray, fog, smoke, low light or nighttime conditions, inclement weather conditions, and the like. For example, an enhanced vision system may utilize real-time radar data in conjunction with one or more terrain databases to render a visualization of a landing zone for helicopter landing during brownout, such that the operator of the helicopter may ascertain the location of terrain features and various non-terrain features, such as other vehicles and buildings, that are proximate to the landing location and not represented by a priori databases.
However, conventional ranging systems produce visually-noisy or low resolution displays. For example, although a radar system can operate well in low visibility conditions, the graphical information obtained from a radar system may not accurately represent the size, shape, and/or visually distinguishable features of an object. In other words, a radar system usually represents objects in a graphically ambiguous manner. Thus, although a member of the flight crew can utilize a ranging system to recognize a likely location of an object, the person is unable to glean detailed information regarding the type and/or configuration of the object. In addition, if the ranging sensor sampling rate (i.e., the rate that the sensor updates) is too low relative to the speed of a moving object, the ranging system may be unable to accurately resolve the moving object. For example, a moving object may appear to jump across the display, appear as being blurred or smeared across the display, or the size of the moving object may be exaggerated. These visually noisy displays increase the perceptual processing and mental workload of the pilot and/or crew to adequately parse the displayed information, thus reducing the potential information superiority to be gained from the enhanced vision system.